What command can be used to generate an internal volume solid?

The command that can be used to generate an internal volume solid is the option that specifically refers to creating inner geometries or filling cavities within a solid model.

In the context of solid modeling, generating an internal volume solid allows designers to create a new solid body that fills or adds material within an existing outer shell or complex geometry. This is particularly useful in creating more complex components where internal structures are needed for manufacturing, functional support, or aesthetic purposes.

The other options provided do not perform this specific function. While "Delete Face" is used to remove surfaces from a solid model, it does not create an internal volume. "Generate Body" is too general and may refer to various creation functions but does not focus on generating internal volumes specifically. "Combine Solids" usually pertains to the merging or subtracting of existing solid bodies, rather than creating a new internal solid structure.

Thus, the most appropriate command for generating an internal volume solid is one that directly addresses the creation of internal geometry, which is typically described by the option that states "Create Interior Solid."